Why Confined Space Fatalities Continue to Happen
More than 30 years after OSHA's confined space standard was introduced, workers continue to die in enclosed spaces. Understanding atmospheric monitoring, rescue planning, and common misconceptions can help close persistent safety gaps.
- By Dennis Terpin
- Sep 14, 2026
Despite decades of rigid OSHA regulations, an average of 100 to 128 workers die each year in confined spaces like silos, tanks, sewers, and other enclosed areas. Recent data from 2011 to 2018 indicates an average of 128 deaths per year, compared to 96 per year between 2005 and 2009, with a consistent increase from 2013 to 2017. Additionally, in 2022, 44 workers died in confined spaces, representing an increase of a 41% from a decade prior.
In this unique webinar, we will explore some interesting concepts which may lead to a better understanding of why 30 years after the original standard was released workers are still dying at such an alarming rate.
- An illusion of safety could be if you can’t see it, touch it, feel it, or smell it can’t hurt you.
- The standard requires that each employer ensure that a competent person identifies all confined spaces in which one or more of the employees it directs may work and identify with each space that is a permit space and is present on site.
- A high volume of untrained workers and "would-be" rescuers, lead to a widespread failure by employers to implement or even understand basic safety procedures.
- Is this statement actually correcting? According to OSHA, a safe level of oxygen in the workplace (Confined Spaces) is between 19.5% and 23.5% by volume. Anything below 19.5% is considered oxygen-deficient and immediately dangerous to life or health, while anything above 23.5% is considered oxygen-enriched and creates extreme fire and explosion hazards.
- Maybe training should be changed to the hazards in and around confined spaces.
- There are two confined space standards, one for general industry and one for construction.
- The permit takes longer to complete that actual job.
- How important is knowing the difference between a bump test, a calibrating and a fresh air calibrating.
- Not understanding your Atmosphere monitoring equipment can lead to immediate safety hazards, including missing toxic gas alerts, equipment failure, or false alarms that cause unnecessary evacuations. Failing to grasp how these protection systems detect changes in air quality risks thus exposing personnel to hazardous environments without warning.
- How long does it take to correctly monitor a 20-foot-deep vertical shaft? If you say less than 5 minutes; you may not fully upstand confined space monitoring.
- What is the 4-foot confine space rule?
- Do you Treat all confined spaces as hazardous?
- You arrive at the scene of a rescue do you ventilate or monitor first; the difference may save a life or two.
During a confine space incident according to NIOSH - 85% of the time a SUPERVISOR was present, 29% of the dead were SUPERVISORS, 31% had WRITTEN Confined Space Entry PROCEDURES, 0% used the WRITTEN PROCEDURES, 15% had Confined Space TRAINING, 0% had a RESCUE PLAN, 60% of "WOULD-BE" RESCUERS died, 95% were AUTHORIZED by supervision, 0% of the spaces were TESTED prior to entry and 0% were VENTILATED.
Join me as we explore these and other confined space gaps which can lead to a Dangerous Illusion of Safety.
This article originally appeared in the September 2026 issue of Occupational Health & Safety.
About the Author
Dennis A. Terpin is a Retired Senior Industrial Hygienist and Emergency Manager at the University of Illinois at Chicago. Dr. Terpin is a member of the ASTM F23.65 committee on Protective Clothing and Respiratory Protection and is a Master Level Instructor for FEMA/DHS at the Center for Domestic Preparedness.